Every box is made up of the following items: Four "sides," always used in the rough except where they join; two "bottoms," smoothly planed on the upper side and at piace of jointure; two boards for capping the "sides," which are strongly nailed to the posts of -the "standards;" four "standards," made of four-by-fours, and consisting of a crosspiece for the "bdttoms," with two uprights for the "sides;" and numberless pine wedges, used in chinking, that the flume may not leak. The above items in place, and the box is fitted for the blocks and chinking.
The blocks used are made of the nutpine of the foot-hills —it being the most durable wood in the vicinity for the purpose —and are simply cross-sections of the tree, partially squared, varying in diameter and thickness; ranging from sixteen to thirty-two inches for the former, and from six to ten inches for the latter.
Each box takes about six of the thir
ty-two-inch blocks, when the flume is a wide one, and a larger number when it is a narrow one, as all boxes have about
the same length. It is evident that, when the blocks are placed in the box, as they are nearly circular, there will be many crevices unfilled. These openings are closely chinked with tunnel-rock, or broken slate bowlders. In doing the chinking, great care is taken that no block be left in a loose condition; for, were one to be left in this manner, the water would uproot the blocks, form a dam, and flood the banks; and, were it to happen in the tunnel, tear away the timbers, and endanger the lives of the miners who tend the same. The work of putting in the blocks and chinking is therefore done by men who are well fitted for it by thorough experience.
The blocks are changed three or four imes a year, as they prove durable or therwise; and are reversed in position t the times of the "clean-ups," as they
are found to wear much faster on the side toward the head of the box—the head of the box meaning the point nearest the head of the flume, or upper end of it. As the result of this frequent changigg, quite an extended block-business is supported in the surrounding country.
After being laid with blocks and chinking, every box is thoroughly lined with boards, for the purpose of keeping the blocks in their places; and, with the further addition of quicksilver, which is deposited in the crevices to absorb the gold, thereby forming amalgam, the flume is ready for use.
A flume completed throughout the tunnel, along the bed of the mine, and over the hills to the brink of the river, is a demand for water—the '"'open sesame"? to the rich treasure of this deposit; and, as there is no water in the vicinity of the mines, it becomes necessary to build ditches, from a far-distant point in the mountains which furnish the supply. These ditches are rarely the exclusive property of the men owning the mines; but are owned by Companies, formed on a stock principle. and who furnish water to the different claims, at such prices as seem most wholesome to their interests. The Yuba River, far up in the mountains, is the source of the supply; and the Excelsior Canal Company the most prominent corporation who represent the business in this district.
Large reservoirs are made at convenient distances from the mines, in places having natural advantages, and that will give sufficient current. These are sometimes wholly, and sometimes in part only, the property of the different Companies they supply, and are built principally to furnish water during the long, dry months of summer and the early fall. It often happens, however, that even this precaution fails to meet the demand, since many of the claims are forced to work on half-rations, and not a few
